Biosynthesis of Glycoconjugate Virus-like Particles (VLPs)

The outermost surface of bacterial pathogens consists primarily of complex carbohydrate structures-polysaccharides, glycolipids, and glycoproteins. To raise a long-lasting and effective immune response against carbohydrate antigens, they generally require covalent attachment to an immunogenic carrier protein-a so-called glycoconjugate vaccine. One hurdle to the development of glycoconjugate vaccines is that carbohydrate antigens remain inaccessible to recombinant production. Thus, the carbohydrate antigen is typically purified from the pathogen and then chemically conjugated to an immunogenic protein. Recent developments in the field of bacterial glycoengineering have opened the opportunity for total recombinant production of glycoconjugate vaccines. In this method, we describe the production of proteinaceous, virus-like particles (VLPs) bearing the conserved N-glycan of Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumoniae.